Aerosol fogging device



Jan. 18, 1966 H, D. JOHNSON AEROSOL FOGGING DEVICE 2 Sheets-Sheec l Filed May i9. 1964 CATTOQNJEY/ w m c Y M @Jarold D. QohnJo/b Jan. 18, 1966 H, D. JOHNSON AEROSOL FOGGING DEVICE 2 Sheets-Sheet 2 Filed May 19, 1964 MVESIQT Ow .D Qjohn royl/ 4% M W2 CATworzloEy/'l L w mv. lla f .0 m Z m X Q 1 Q 2 2 8 2. Z

United States Patent O 3,229,409 AEROSOL FOGGING DEVICE Harold D. Johnson, Emmetsburg, Iowa, assigner to Aero- Dyne Corporation, Emmetshurg, Iowa, a corporation of Iowa Filed May 19, 1964, Ser. No. 368,583 9 Claims. (Cl. 43-129) The present invention relates to aerosol dispensers and more particularly -to a self-contained hand-held dispenser particularly well suited to the dispensing of aerosol in secticlde and the like.

In prior H. D. Johnson et al. Patent 3,074,199, there is disclosed an aerosol dispenser of the hand-held type capable of [generating large volumes of insecticide fog consisting of pyrethrins and the like dissolved in a vaporizable mineral oil with the droplets being sufciently small so as to tend to remain in air suspension yet large enough to have a lethal effect upon any insects which may be contacted by the fog. The device disclosed herein was develope-d for the purpose of improving the efficiency, effectiveness, convenience and safety of the prior construction.

Consequently it is an object of the present invention to provide a fogging device for use with a tank of liquified gas having a threaded connection and self-contained check valve in which a novel valve mechanism is provided lfor effectively controlling the rate of flow of the gas to the burner but which insures that no gas will be lost either as a result of seepage through the threaded joint or as a result of leakage through the frame of the device during periods of non-use.

It is another object of the present invention to provide a frame and burner structure which is more compact, lighter in weight, and less expensive than the prior device and which is thermally more eieient utilizing a larger proportion of the heat theoretically available in the gas for producing vaporization of the aerosol liquid in the vaporizing coil.

It is another object of the present invention lto provide an aerosol fogging device which is capable of operating efficiently over a wide range of temperature and pressure of gas in the gas tank. Thus it is an object to overcome the effect of the usual temperature and pressure drop resulting from vaporization in the tank and which is particularly troublesome yat full output. It is therefore an object to provide a fogging device which may be efficiently operated over a relatively wide range in the Btu. or heat rate tailored to the amount of fog required. This makes it possible to use the fogging device out of doors where an extremely large volume of fog may be produced with the device operating at its maxi-mum rate or indoors, in confined spaces, where only a fraction of full fog output is required.

It is another object of the present invention to provide a fogging device which need not be held in upraised pistolgrip fashion but which may be supported pendulously with the users arm in a natural, lowered position enabling use for hours at a time without discomfort or fatigue.

It is another object of the present invention to provide a fogging device which is easy to light, which operates quietly -free of the rushing noise which characterizes the operation of the prior devices and which may be used with complete safety by all householders, even by Women and children, and raising the level of usage of the device to that of a household necessity.

Other objects and advantages of the invention will become apparent upon reading the attached detailed description and upon reference to the drawings in which:

FIGURE 1 is a general perspective view of a fogging device constructed in accordance with the present invention.

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FIG. 2 is a longitudinal section taken vertically through the structure of FIG. 1.

FIG. 2a is a fragmentary horizontal section taken along the line 2a-2a in FIG. 2 showing the gas porting arrangement.

FIG. 3 is a fragmentary section taken along line 3-3 in FIG. 2 showing the burner tube mounting.

FIG. 4 is an enlarged fragmentary section taken along the line 4 -4 in FIG. 2 showing the check valve in the gas tank depressed for throttled discharge of gas to the burner.

FIG. 5 is a fragmentary section similar to FIG. 4 but showing the check valve in the off condition to preclude leakage of gas during periods of non-use.

FIG. 6 is a fragmentary section showing the use of adapters to enable use of low pressure hutane containers as contrasted with the higher pressure propane tanks.

While the invention has been described in connection with certain preferred embodiments, it will be understood that I do not intend to be limited to the embodiments shown -but intend to cover the various alternative and equivalent constructions included within the spirit and scope of the appended claims.

Turning now to the drawings, the present fogging device has a frame or valve body 10 in the form of a die casting or the like having a lower horizontal portion 12 and a front vertical portion 13 in L formation. Extending archingly from the front to the rear of the device is a carrying handle 14 surrounding a central gripping space 15. Projecting forwardly from the front surface of `the frame is a burner tube 16 having a series of vents 17 in the yform of transverse slots and terminating in a nozzle 18 from which the fog is discharged. The discharge is controlled by a valve 20 which is positioned in the forward end of the handle 14 for convenient manipulation by the thumb of the user. Depending from the frame 10 is a first tank 21 which holds a charge of liquiiied gas, for example, propane, and a second tank 22 which holds the :aerosol liquid.

The invention contemplates the use of a propane tank 21 of conventional type having a threaded coupling 23 at the upper end with a self-contained check valve 24 having a spring 24a and terminating in a central valve stern 25. The valve 24 may, for example, be of the same type as is used in automobile tires. The tank also includes a safety valve permitting relief of excess pressure which might occur, for example, where the tank is stored in a hot place; the latter, however, forms no part of the present invention. The companion tank 22 including a charge 26 of aerosol liquid is similar to the tank 21 except that it does not have a check valve and the throat indicated at 27 is sufficiently wide so as to admit a dip tube 28 which conducts liquid from the bottom of the tank. In the discussion which follows it may be assumed that the charge of aerosol liquid 26 consists of insecticides such as pyrethrins dissolved in a mixture of light mineral oils having a range of vaporization temperature.

For securing the tanks 21, 22, threaded receptacles 31, 32 having gaskets 31a, 32a are provided on the undersurface of the frame. Attention will first be given to the vaporizing coil and the means for conducting aerosol liquid from the tank 22 to the coil, following which the gas conducting and controlling arrangement will be discussed.

Thus coiled within the burner tube 16 is a vaporizing coil 33 in the form of a helix of small diameter tubing made of heat resistant steel or the like having an inlet 24 which is secured to the forward face of the frame by a fitting 35. For the purpose of conducting the aerosol liquid upwardly from the tank Z1, the dip tube Z8 is secured to a nipple 36 which is screwed into the lower end of a vertical passageway 37. The nipple has a downwardly projecting portion 38, to which the upper end of the dip tube is secured, having a central metering orice 39.

The valve 20 serves to control the escape of the aerosol liquid from the space 37. The valve thus includes a valve assembly 40 having a valve stem 41 carrying a valve member 42 which cooperates with a valve seat 43. The valve stem is normally urged into the closed position by a coil spring 44 and sealing at the valve surfaces is assured by a small O-ring or the like 45. The upper end of the valve stem is engaged by the lower end of the valve plunger 20 which passes through a suitable packing gland 46. The valve plunger has sufficient clearance so that when the valve stern 41 is unseated, aerosol liquid is free to flow into the space 37 past the valve seat and out through a horizontal passageway 47 into the vaporizing coil 33.

In the above paragraph it has been assumed that pressure exists in the aerosol tank 21 suicient to force the aerosol liquid up the `dip tube 28 and through the metering orifice 39 when the valve plunger 20 is depressed; the means for pressurizing the tank 22 will be discussed at a later point.

Turning attention next to the burner supply, the burner generally indicated at 50 is centered within the burner tube and connected to the frame or valve body at a connection -1 which may, for example, be a simple telescoped joint. For the purpose of conducting gas to the burner, a horizontal port or passageway 52 is provided in the valve body having an offset 53 (-see FIG. 2a) which serves to conduct the gas around the vertical space 37 previously referred to. Provision for the offset 53 is made in the die casting.

To conduct the gas upwardly from the gas tank 21 into the passageway 52, a gas nipple 55 is provided having an upper end 56 which is threaded into the valve body and'having a downwardly extending portion 57 which extends, as shown, into the upper end of the tank 21. The nipple serves, incidentally, to hold in place the gasket 31a.

In accordance with the teachings of the earlier patent mentioned above the pressure of the gas in the passageway 52 leading to the burner 50 is utilized for pressurizing an aerosol liquid in the tank 21. Thus an auxiliary port 60 is provided in the valve housing connecting the gas passageway 52 with the upper portion of the aerosol liquid tank 22. In order to provide a pressure differential between the pressure in the passageway 52 and the tank and to prevent reverse flow of liquid into the passageway 52 when the device is inverted, a check valve is fitted into the port 60. The check valve 61 is also used to prevent the pressure in tank 22 from escaping back into passageway 52 and then to the burner. This would keep the burner operating even when tank 21 is turned off The check valve includes a valve member 61 in the form of a small cylinder of soft plastic pressed against a seat 62 by a coil spring 63 seated on a retainer 64. This arrangement has the advantage that the pressure exerted on the aerosol liquid is coordinated with the pressure of the gas being fed to the burner as discussed in some detail in my prior patent. However, in carrying out the present invention it is not necessary to utilize pressure from the gas cylinder for displacing the aerosol liquid and, if desired, a small amount of liquied gas may be charged into the liquid tank 22 to provide the necessary propulsive effect.

In accordance with one of the aspects of the present invention a novel burner structure is provided having an asperating portion and a burner portion in adjacent chambers within the burner tube. Thus I provide a burner element having a first or aspirating portion 65 and a burner portion 66 separated by a 4disc 67 which fits closely within the burner tube and which divides the space within the burner tube into two adjacent chambers. Mounted in the fitting 51 on the valve body is a burner nozzle 68 having a small aperture so that a stream of gas is directed centrally within the burner element past aspirating openings 69. The burner tube is left open at its rear end (see FIG. 3) so that air is free to enter. The gas-air mix ows into the burner portion 66 which is fitted with a series of burner ports in the form of narrow transverse slots S spaced from one another along the length of the vaporizing coil 33. It is found that a distributed series of burner ports of relatively small area distributes the heat more evenly along the length of the vaporizing coil and the operation tends to be more silent than in prior art construction completely free of any popping or sputtering. Moreover it is found that the burner described above is more easily lit than the prior construction, even when cold, simply by holding a match over the vent openings 17 or with a spark lighter and without necessity for any temporary throttling of the aspirated air.

In accordance with an important aspect of the present invention novel means are provided for a throttled control of the gas from the gas tank 22 utilizing the check valve 24 and valve stem 25 already included as a standard part of the tank. Thus in accordance with the invention I provide a gas valve plunger which is centered with respect to the gas tank receptacle 31, which extends into the tank for actuation of the valve stem and which has means at its upper end, under manual control, for determining the plunger position and hence the amount that the check valve 24 is cracked open. This control can be rotated in either direction, eliminating the need for arrows indicating direction to turn on or o More specifically in accordance with the invention I provide, in addition to the valve plunger, a control rod having a control knob at its outer end for manual manipulation and having an eccentric at its inner end for directly engaging and positioning the plunger. Thus turning to the drawings I provide within the nipple 55 a valve plunger 70 having a head 71 at its upper end and having its lower end 72 in contact with the upper end of the valve stem 25. Extending transversely above the gas valve plunger and preferably alined with the gas passageway 52 is a control rod 73 which is sealed by a packing gland 74 and which has an adjusting knob 75 at its outer end. The rod is formed, at its inner end, with a cam surface 76 which may be rotated around into engagement with the plunger 70 as shown in FIG. 4 unseating the valve 24. Clearance is provided at 77 between the plunger 70 and the inner wall of the nipple for passage of the liberated gas upwardly into the passageway 52 through which the gas iiows to the burner nozzle 68. Preferably the throw of the eccentric '76 is suicient so that the valve 24 is fully uuseated when a maximum heat rate is desired as, for example, when the fogging device is used out of doors. Preferably also a certain amount of lost motion is provided in the cam connection resulting in a dead band as indicated at 80 (see FIG. 5). As a result it is not necessary to set the knob 75 accurately to the olf position; a position anywhere within the range 80 is sufficient to break the connection between the cam and the upper end of the valve plunger, thereby insuring that the vlave 24 is fully seated by its spring 24a and preventing any leakage of gas during periods of non-use.

As a result of the novel valving arrangement the expense of providing a separate, gas-tight valve in the body of the device is avoided and no reliance need be placed upon the gas-tight integrity of the die casting which forms the frame or valve body. This is to be contrasted with prior devices in which pressure was applied on the pressure side of the shut-off valve continuously under standby conditions, as long as the tank remained screwed in, thereby leaking the high pressure gas through any porosity which might exist in casting or through the threaded joint. The above described improvement insures that a user will not be disappointed by having an empty tank at a time when the fogger may be most needed, or create any hazard due to leakage of ilammable gas.

The open ended burner tube 16 is cooled on the mounting end by the large amount of air aspirated by the burner. In addition, the vaporizable liquid passes through a section of the handle close to the point to which the burner tube is attached; the two effects help keep the handle cooled from any heat transmitted by the heated elements.

For the purpose of permitting free llow of aspirated air into the rear end of the burner tube while nevertheless securing the burner tube iirmly to the valve body, bosses or lands 81 and 82 are preferably provided at the front of the valve body and integral therewith having an upper and lower arcuate contour which mates with the inner surface of the burner tube. The bosses may be provided with radially extending protuberances S3, 84 which iit into registering openings punched into the rear edge of the burner tube. To install the burner tube it is suiiicient to apply lateral pressure as indicated by the arrows in FIG. 3 thereby deforming the rear end of the burner tube temporarily into oval position so that the protuberances are cleared, and, upon release of pressure, the normal resilience of the tube causes it to resume its original shape thus locking the tube in position. The process may be reversed for removal.

While the structure and operation of the device Will be apparent from the above description, the operation may be summarized as follows: a tank 21 containing liquified gas, for example, propane and a tank 22 containing an aerosol liquid are screwed into place in the threaded receptacles 31, 32. Turning the knob 75 from the oi position cams the valve plunger 70 downwardly into contact with the valve Stem 25 in the tank 21 thereby permitting flow of gas through the passageway 52 to the burner nozzle 68. Because of the small aperture in the nozzle, back pressure is built up in the passageway 52 which is applied through the auxiliary port 60 to the space above the liquid level in the tank 22 thereby tending to force the -liquid up through the dip tube 28. The gas passing from the nozzle aspirates air through the openings 69 so that air-gas mix escapes through the burner ports for convenient lighting by a match held above the vents 17. Allowing a few seconds for the vaporizing coil 33 to come up to temperature, the discharge valve plunger 20 is depressed, permitting the pressurized aerosol liquid to ilow into the inlet of the vaporizing coil. As discussed in the prior patent mentioned above, the lighter fractions of the liquid are vaporized first creating vapor which expands producing turbulence within the vaporizing coil and forcing the still liquid components along the length of the coil until a temperature is reached where they are atomized into tiny droplets. The liquid is never completely vaporized. As an example, the fog as it leaves the nozzle is about 350 F., while the boiling point of the base oil is about 500 F. In fact, the drop size of the efiluent can be controlled by controlling the temperature at the nozzle. The higher the nozzle temperature, the more complete the vaporization and the smaller the drop size and vice versa. By the time that the aerosol material reaches the nozzle 1S it has been fully converted to tiny droplets propelled by vapor and it is discharged in the form of a voluminous fog in which the particle size is at or near optimum. Where it is desired to create the maximum amount of fog as, for example, when treating outdoor acreage, the control knob 75 may be turned to the full on position getting maximum burner heat and the discharge plunger may be kept depressed. However, where desired to release as lesser volume of fog the knob 75 may be turned to a point approaching the oit position where throttling occurs so that only a small amount of gas is liberated at the burner and with the valve plunger 20 being pressed in short spurts to provide burst of fog. The settings of the two control elements are not at all critical and a few minutes usage suices to determine the proper setting of the knob 75 and manipulation of the plunger 20.

The burner is found to operate eiciently and reliably over a wide range of gas pressure. Moreover, if desired, low pressure butane may be used as fuel without modication of the valve body and simply by using appropriately threaded adapter plugs 11, 92 as shown in FIG. 6, or by filling the standard tanks with low pressure gas for use in overseas areas or localities with only low pressure gas available. in this figure to indicate corresponding parts. 66 having a different slot width may be used.

The present construction is not only distinguished by prevention of leakage and high thermal eiciency but experience shows that it is more convenient to use and may be held for longer periods of time without discomfort or fatigue which is particularly advantageous in commercial and municipal usage. Thus the device may be held in a natural pendulous position, with the tanks providing a righting force so that the burner tube itself is kept substantially horizontal without intentional effort on the part of the operator. Moreover the handle 14 which extends bridgingly over the valve body provides a natural grip for operation of the plunger 20 by the thumb of the user. The gas control knob is, moreover, located safely at the rear of the device so that it is not affected by branches or underbrush which might come in contact with the device in the iield.

If ordinary precautions are employed the device is completely safe and does not' constitute a tire hazard. It is one of the features of the present burner design that the flame is completely contained within the burner tube with the products of combustion being kept separate from the etliuent from the nozzle 18 so that there is no risk of the effluent catching tire. Moreover the burner operates quietly, free of any tendency toward backring or the like which might startle the user.

While the construction and operation has been described in connection with insecticide, the device may be used to dispense many other materials such as deoderizing agents, perfumes, tear gases, fumigants, repellants and germicidal agents suspended in a wide variety of vaporizable liquids such as alcohol, water, glycol, chlorinated hydrocarbons, and combinations of miscible liquids.

It will also be apparent to one skilled in the art that while the device is capable of taking care of fogging jobs usually requiring much larger equipment, the device is simple and compact consisting of a minimum num-ber of simply formed parts and may be manufactured at such low expense that .a unit may be afforded by any household.

I claim as my invention:

1. In an aerosol fogging device for use with a tank of liquitied gas having a threaded coupling with a self-contained check valve and a central valve stem and a companion tank of areosol liquid, the combination comprising A burner a frame having threaded receptacles for the gas tank and aerosol liquid tank respectively, a 4burner tube on the frame, a vaporizer coil in Ithe burner tube having an associated discharge valve for connecting the inlet end of the coil to the receptacle for the aerosol liquid tank, means .for pressurizing the latter, a -gas burner in said tube, means dening a horizontal gas passageway in the said frame connected to the burner at one end and having a right-angled connection to the gas tank receptacle at the other end, a plunger centered in the vgas tank receptacle for engaging the upper end of the valve stem of the tank, a cont-rol shaft in said horizontal passageway having a knob at its outer end and having a cam at its inner end overlying the end of the plunger so that when the knob is turned the cam controllably presses the plunger into engagement with the valve stem for progressively unseating the valve `in the tank for throttling the gas for metered escape thereof to the burner.

2. In an aerosol fogging device for use with a tank of liquied gas having a threaded coupling with a self-contained check valve and .a central valve stem and a companion tank of aerosol liquid, the combination comprising Corresponding reference numerals are used.

7 a frame formed Wi-th adjacent threaded receptacles for the gasvtank'and aer-osol liquid tank respectively, a burner tube at the `forward end of the frame, a vaporizing coil in the burner tube havin-g an associated discharge valve at the front end of the frame for connecting the inlet end of the coil -to the receptacle for the aerosol liquid tank, means for pressurizing the latter, a burner in the tube, means defining a gas passageway in said frame for connecting the gas tank receptacle to the burner, said frame having a bore centered in the lgas tank receptacle,

a plunger in said bore, said frame including a handle extending in arched position between the ends of the frame, and a manual control shaft at the base of the handle at the rear end of the frame having a cam at its forward end .for engaging the upper end of the plun-ger and having a knob at its rear end projecting from the frame for thrott-ling adjusting the rate of gas flow.

3. In an aerosol fogging dev-ice for use with a tank of liquiiied gas having a threaded coupling with a self-contained check valve and a central valve stem and a companion tank of aerosol liquid, the combination comprising a horizontal frame having a forward end and a rear end, said frame having receptacles on the underside for threaded reception of the -gas tank and aerosol liquid tank `respectively, a burner tube at the forward end of the frame and extending horizontally therefrom, a barrier in the .burner tube separating the same into an aspirator chamber and a burner chamber, a vaporizing coil in the burner chamber having an associated discharge valve in the frame for connecting the inlet end of the coil to the receptacle for the aerosol liquid tank for supplying of aerosol liquid to the coil, an aspirator stem on said frame projecting into the aspirator chamber and terminating in a burner extending longitudinally into said burner chamber, means defining a passageway in said frame for connecting the aspirator stern with the gas tank receptacle, a plunger centered in the gas tank receptacle having manual control means for progressively unseating the valve in the gas tank for throttled escape of gas therefrom at a controlled rate.

4. In an aerosol fogging device for use with a tank of liquiiied gas having a threaded coupling with a selfcontained check valve and central valve stem and a companion tank of aerosol liquid, the combination comprising a frame having threaded receptacles on the underside for screwing on a gas tank and aerosol liquid tank respectively, a burner tube extending horizontally at the front end of the frame and having a barrier therein delining an aspirating chamber and a burner chamber, a vaporizing 'coil in the burner chamber having 'an associated discharge va-lve in the frame for connecting the inlet end of the coil to the receptacle for the aerosol liquid tank, means for pressurizing the aerosol liquid tank, an aspirator stem extending horizontally'from the fr-ont front of the frame into the aspirator chamber, means defining a passageway in the frame for connecting the gas tank receptacle to the aspirator stem, a plunger centered in the gas tank receptacle for engaging the valve stem for unseating the valve to produce a flow of gas into the aspirator stem, a burner extending horizontally in the burner chamber and connected to -the aspirator stem, said frame having lands spaced above and below the stem for engaging the presented end of the burner tube while leaving the -major portion of the burner tube open for access of air to the aspirating stem.

5. In 'an aerosol fogging device for use with a tank of liquified gas having a threaded coupling with a selfcontained check valve and central valve stem and a companion tank of aerosol liquid, the combination comprising -a frame having threaded receptacles on the underside for screwing in the gas tank and aerosol liquid tank, a burner tube secured to the front end of the frame and extending horizontally therefrom, a vaporizer coil in Athe burner tube having an associated discharge valve in the frame for connecting the inlet end of the vaporizer coil to the receptacle for the aerosol liquid tank, means for pressurizing the aerosol liquid tank, a burner secured to the front end of the frame and extending axially in said .burner tube, means on said frame defining a horizontal passageway connected to the burner at its front end and communicating with the gas tank receptacle at its rear end, a plunger centered in -the gas tank recep-tacle and engaging the valve stem in the gas tank, means for controllably depressing the plunger for escape of gas into the Iburner, said burner having aspirating openings adjacent the point 4of connection with the frame for aspirating air and having burner openings distributed the remaining length thereof and co-extensive with the vaporizer coil for heating of the latter to produce progressive vaporization of the aerosol liquid,

6. In an aerosol fogging device for use with a tank of liquefied gas having a threaded coupling with a selfcontained check valve and central valve stem and companion tank of aerosol liquid, the combination comprising a horizontally extending frame having a lower portion and a front mounting surface, a handle archingly extending over the frame, threaded receptacles in the lower portion for screwing in the gas tank and aerosol liquid tank respectively, a burner tube secured to the mounting surface and extending horizontally therefrom, a vaporizer coil having horizontally spaced convolutions in said burner tube, a burner secured to the mounting surface and extending centrally within the vaporizer coil, means in said frame defining an aerosol liquid passageway between the aerosol tank receptacle and the inlet end of the coil, means for pressurizing the aerosol liquid, a discharge control valve interposed in the aerosol liquid passageway, said discharge control valve being in the form of a valve plunger vertically mounted in the forward portion of the frame and having an operating knob extending upwardly adjacent said handle for convenient manipulation by the operator, means defining a horizontal gas passageway in said frame interconnecting the burner and the gas tank receptacle, a valve plunger centered with respect to the gas tank receptacle for engaging the upper end of the valve stem in the tank, manual means for adjusting the position of the plunger thereby throttlingly to adjust the flow of gas from the tank to the burner, said manual means being in the form of a control shaft extending horizontally in the frame having a control knob at its outer end and extending into engagement with the valve plunger at its inner end.

7. In an aerosol fogging device for use with a tank of liquefied gas having a threaded coupling with a selfcontained check valve and central valve stem and a companion tank of aerosol liquid, the combination comprising a valve body, threaded receptacles in said valve body for receiving the tanks of liquefied gas and aerosol, a burner tube secured to the valve body and projecting horzontally therefrom, a vaporizing coil of helical configuration in the burner tube, a burner Within said burner tube, said burner being in the form of an elongated hollow burner element having a burner nozzle at one end, means including the gas valve and a discharge valve for connecting the gas tank and aerosol tank to the burner nozzle and vaporizing coil respectively, said burner element having a disc mounted thereon for separating the space within the burner tube into an aspirating chamber and a burner chamber, the burner element being provided With aspirating openings in the aspirating chamber and provided with a series of burner ports distributed along the length thereof adjacent the convolutions of the vaporizing coil.

8. In an aerosol fogging device for use with a tank of liquefied gas and a tank of aerosol liquid, the combination comprising a valve body, threaded receptacles in said valve body for receiving the tanks of liquefied gas and aerosol, a burner tube secured to the valve body and projecting horizontally therefrom, a vaporizing coil in the burner tube having an inlet end and a discharge tip and Wound in cylindrical formation to define a central space, and means including a manual valve `for conducting aerosol liquid from the tank to the inlet end of the vaporizing coil, a gas burner in the form of a tube mounted on the valve body and extending axially into the space Within the vaporizing coil, means including a valve member for conducting gas from the gas tank to the burner, a disc surrounding the mid portion of the burner for dividing the space Within the burner tube into an aspirating chamber and a combustion chamber, said burner having aspirating openings in said aspirating chamber and having ports distributed along the length thereof in the combustion chamber for liberation of heat within the burner coil.

9. In an aerosol fogging device for use with a tank of liquefied gas having a threaded coupling with a selfcontained check valve and a companion tank of aerosol liquid, the combination comprising a valve body, threaded receptacles in said valve body for receiving the tanks of liquefied gas and aerosol, a burner tube secured to the valve body and projecting horizontally therefrom, a vaporizing coil of helical configuration in the burner tube having an inlet end and a discharge tip and defining a central space, means including a manual control valve for conducting aerosol liquid from the liquid tank to the inlet end of the tube, a gas burner secured to the valve body and extending axially into the space Within the vaporizing coil, means including a nozzle at the base of the burner for conducting gas from the gas tank to the burner, means dening aspirating openings associated with the nozzle, said burner being formed with combustion ports on the underside of the burner and distributed along the convolutions of the vaporizing coil for even and direct application of heat to the latter, said burner being closed at its forward end, and vents along the upper surface of the burner tube for venting the products of combustion.

References Cited by the Examiner UNITED STATES PATENTS 734,229 7 1903 Hardinge.

794,972 7/19054 Estep 158-120 X 1,053,292 2/1913 Jones. 1,667,613 4/1928 Tilley 158-120 X 2,483,081 9/1949 Wrigley 158-12() X 3,074,199 l/l963 Johnson et al. 43-129 3,134,191 5/1964 Davis 43-129 FOREIGN PATENTS 1,159,717 12/1963 Germany.

SAMUEL KOREN, Primary Examiner.

R. L. HOLLISTER, Assistant Examiner. 

7. IN AN AEROSOL FOGGING DEVICE FOR USE WITH A TANK OF LIQUEFIED GAS HAVING A THREADED COUPLING WITH A SELFCONTAINED CHECK VALVE AND CENTRAL VALVE STEM AND A COMPANION TANK OF AEROSOL LIQUID, THE COMBINATION COMPRISING A VALVE BODY, THREADED RECEPTACLES IN SAID VALVE BODY FOR RECEIVING THE TANKS OF LIQUEFIED GAS AND AEROSOL, A BURNER TUBE SECURED TO THE VALVE BODY AND PROJECTING HORIZONTALLY THEREFROM, A VAPORIZING COIL OF HELICAL CONFIGURATION IN THE BURNER TUBE, A BURNER WITHIN SAID BURNER TUBE, SAID BURNER BEING IN THE FORM OF AN ELONGATED HOLLOW BURNER INCLUDING THE GAS VALVE AND A DISCHARGE VALVE FOR MEANS INCLUDING THE GAS VALVE AND A DISCHARGE VALVE FOR 